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Old 05-31-2013
rmeador rmeador is offline
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Re: Shore GFCI trips when plugging in boat

Much of my boat's electrical system is original (or at least old), but it appears to be in good shape. The boat was surveyed only 2.5 years ago, and I've also done a decent amount electrical work to improve it (I'm an electrical engineer). There was a permanently installed bridge between neutral and ground in the electrical panel, but I removed that at the time I installed the inverter for exactly the reason you mentioned. I verified with a meter at that time that there were no other connections between those lines. If there is something going wrong in the charger/inverter, it must be only when it is turned on, and likely very brief. The inverter supposedly only connects neutral and ground when it is actually inverting, it disconnects them when it is passing through shore power, per the electrical code. I'm at a loss to figure out how to diagnose this, since there is no bridge when it is powered down, and in either shore or inverter powered configuration, there's supposed to be a bridge (it's just a matter of where, which a meter can't tell me).

The yard owner reported that these GFCIs are extremely sensitive and many people have trouble with them. That doesn't mean they're broken, just difficult. Also, none of the GFCIs within my boat ever trip... I'm not sure if they would if the fault is upstream of them though.
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